This invention relates to headrest-mounting-tubes, for use in connection with automotive seats. Such tubes are shown, for example, in patent publication U.S. Pat. No. 6,035,516 (Petersen, March 2000).
Headrests for vehicle seats have two posts protruding downwards, and these posts engage in headrest-mounting-tubes that are attached to the top-rail of the seatframe. In the past, it has been the common practice to attach the headrest-mounting-tubes to the top-rail by welding.
However, the recent trend is to attach the tubes to the top-rail by a cold-forming method. The top-rail of the seatframe is mounted in a die, and the headrest-mounting-tube is subjected to a punching force exerted in the axial sense relative to the tube, whereby the metal of the tube engages with the top-rail, and crumples and folds, in such manner as to leave the tube firmly secured to the top-rail, as shown in the said U.S. Pat. No. 6,035,516, this manner of securement being termed lock-beading. As will be explained, the present invention is particularly applicable to forming the keyway-pockets in the headrest-mounting-tubes when the headrest-mounting-tubes are secured into the seatframe by lock-beading.
A typical automotive headrest is adjustable, and often the manner of adjustment is such that an adjustment operator is located on the headrest post. In order to make an adjustment, the driver reaches behind his head and operates the adjuster by feel. The designer must make sure that the adjustment operator is presented to the driver always in the same orientation. For this and other reasons, it is a common requirement that the headrest-mounting-tube should have a slot or keyway formed therein, which can be engaged by the adjustment operator associated with the headrest post, to ensure the correct orientation thereof.
The invention concerns the slot or keyway in the headrest-mounting-tube, and the manner in which the same can be formed.